Keyboard works too. Use ^ for powers. Factorial uses a whole number from 0 through 170.
Separate values with commas or spaces. Leave frequency blank for a regular list. Sx is for a sample. sigma x is for a population.
Leave the lower box blank for -infinity or the upper box blank for +infinity.
Intervals estimate. Tests check a claim. Pick the tool that matches the problem.
This uses the unpooled (Pooled: No) method.