diff --git a/35_IntroToHPC/main.md b/35_IntroToHPC/main.md
index 1badb7a..726ba90 100644
--- a/35_IntroToHPC/main.md
+++ b/35_IntroToHPC/main.md
@@ -102,6 +102,12 @@ Activities where participants all actively work to foster an environment which e
 </div>
 
 
+### Which statement is generally true about what we mean by a "cluster"?
+- A. One very powerful computer
+- B. Many geographically dispersed computers connected via the internet
+- C. Network of CPU nodes with lots of RAM that are linked together with some kind of network
+
+
 ### Network/fabric
 - Network/fabric - the means of communication between nodes
   - Communication lines usually fiber/copper/wireless
@@ -112,6 +118,11 @@ Activities where participants all actively work to foster an environment which e
   - Ethernet -- 0.1ms -- \~1-40 Gbit/s -- network
   - Infiniband -- 0.001ms -- \~100-800 Gbit/s -- fabric
 
+### Which statement is false?
+- A. Latency is the time between sending and receiving messages
+- B. Bandwidth is the rate at which messages can be sent
+- C. Infiniband fabric has relatively 'high' latency and 'low' bandwidth
+
 
 ### Compute nodes
 <div style="display: flex;">
@@ -137,6 +148,12 @@ Activities where participants all actively work to foster an environment which e
   - Cores typically slower than laptop/workstation cores, but more of them and more cache/RAM
 
 
+### Which statement is true about nodes and cores?
+- A. There is one node per supercomputer
+- B. Each node has multiple CPU cores
+- C. Cores in supercomputers are typically faster than laptop cores and have less RAM
+
+
 ### Compute node architecture -- `lstopo`
 - Cores also sometimes have extra groupings in `NUMA` (non-uniform memory architecture) domains
   - Tells what hardware has direct access to what memory
@@ -205,6 +222,12 @@ Activities where participants all actively work to foster an environment which e
 - A handful of GPUs for special purposes
 
 
+### Rusty/popeye storage -- local
+- All worker nodes have fast `NVMe` storage local to the machine
+- Usually about 2 terabytes in the `/tmp` path
+- Automatically deleted at job completion!
+
+
 ### Rusty/popeye storage -- home
 - `/mnt/home/$USER` AKA `$HOME` -- default path
 - Put your source code and software installs here!
@@ -244,6 +267,13 @@ Activities where participants all actively work to foster an environment which e
 https://wiki.flatironinstitute.org/SCC/Hardware/Storage
 
 
+### Which statement is true about file systems at FI?
+- A. I should put many small files ina  single directory on ceph
+- B. I should put large files in my home directory
+- C. Home and ceph are the only options for storing data during a job
+- D. Files stored in my home directory are backed up while ones on ceph are not
+
+
 
 ## Environment management
 
@@ -302,6 +332,7 @@ python pi.py 100000 0
 - We could make our code more efficient...
 - But let's throw some power at it, some options are:
   - `MPI` (message passing interface) using `openmpi`
+  - `srun` to run multiple copies
   - multiple serial jobs via `disBatch`
   - could loop through calls to python in sbatch script, but hard to balance and error prone
   - could use small jobs or job array with slurm, but this angers the compute gods