What would each of the following expressions evaluate to? Write your guesses in the space provided, and then take turns typing them into the computer.

(+ 1 4) will be 5

(> 0 5) will be true

(/ 4 2) will be 2

(= 1 9) will be false

(- 0 9) will be -9

(<= 2 2) will be true

(string-length "bat") will be 3

(string=? "dog" "cat") will be false

1) What does the function < do?

2) What does the function (string=?) do?

3) Write the contract for these Boolean functions in your Contracts page.

4) How many Numbers are there in the entire universe?

5) How many Strings are there in the entire universe?

6) How many Images are there in the entire universe?

7) How many Booleans are there in the Universe?

What are they?

These materials were developed partly through support of the National Science Foundation, (awards 1042210, 1535276, 1648684, and 1738598). CCbadge BS:Games by Jen Poole, Emmanuel Schanzer, Ed Campos Jr, and Dorai Sitaram is licensed under a Creative Commons 4.0 Unported License. Based on a work at www.BootstrapWorld.org. Permissions beyond the scope of this license may be available by contacting schanzer@BootstrapWorld.org.