Here are some quick self-check problems.
After each lecture, I will try to post one or two
short questions that you should be able to answer
based on the previous lecture material.
**These are problems that you should be
able to answer before the beginning of the next lecture.**

Please do not ask me to post the solutions to these problems.
**Do not ask about these problems on the Learn discussion forum.**
The purpose here is for you as an individual to determine if you have understood
the previous material, and that you can create your own solution.
In most cases, you should know if your answer is correct
by typing in a solution in DrRacket.

If you are unable to come up with your own solutions for these
problems then I encourage you to visit office hours,
**as soon as possible**, to make
sure you understand the material from the course.
You are also welcome to bring your answers to the
problems to office hours to confirm that they are
good solutions.

- Lecture 4 - Tuesday, September 17
- In many tournaments, competitors are awarded points as follows:

2 points for a win, 1 point for a tie, and 0 points for a loss.

Write a function called**round-robin-pts**that consumes three parameters:**num-wins**,**num-losses**, and**games-played**, and produces the number of points earned according to the rule described.

Include all design recipe components in your solution. - Write a function called
**point-differential**that consumes the number of wins, losses, and games played for two teams (a total of 6 parameters), and produces the difference between the points the two teams earned as described above. The result should be a non-negative integer. The built-in function**abs**will be useful. Use the function**round-robin-pts**as a helper function in your solution.

- Lecture 3 - Thursday, September 12
- E = mc
^{2}is probably the most famous equation in the world describing Albert Einstein's theory of special relativity.

The**E**represents kinetic energy, the**m**represents mass, and**c**represents the speed of light. - Define a constant called
**speed-of-light**that is set to 299792458, representing the speed of light in metres per second. - Define a function called
**kinetic-energy**that consumes a single parameter representing the mass of an object, and produces the value equivalent to the**E**in Einstein's equation. - Assuming that you have defined the constant and function described above,
trace this Racket expression using the substitution rules described in Module 1.

`(kinetic-energy 1000)`

- Lecture 2 - Tuesday, September 10
- Define a function called
`perimeter`

, that consumes two parameters,`r-length`

and`r-width`

, representing the dimensions of a rectangle and produces the perimeter of the rectangle. Remember that the perimeter of a rectangle is the sum of the lengths of the sides of the rectangle. - Lecture 1 - Thursday, September 5
- Convert these expressions to valid Racket expressions:
- 2 * -4 * 5
- 6 - 12/3 + 4 * (9 - 1)
- (4 + 3)/(12 -7)
- Evaluate this Racket expression (without using the computer):
- (- (* 3 12) (+ (* 4 5) 1))