Answer:
a) WCK, WTM, WTK, BCM, BCK, BTM, BTK.
b) 1/4
Step-by-step explanation:
a)
For this answer we just need to write all possibilities of sandwiches, so we can use the options given to create all the sandwiches, besides the one given:
(WCM given), WCK, WTM, WTK, BCM, BCK, BTM, BTK.
b)
From the letter a), we have 8 possible options. From these options, we have 2 that have turkey and ketchup (WTK and BTK), so the probability is the number of options we want over the total number of options:
P = 2/8 = 1/4
Consider such events:
A - slip with number 3 is chosen;
B - the sum of numbers is 4.
You have to count 
Use formula for conditional probability:

1. The event
consists in selecting two slips, first is 3 and second should be 1, because the sum is 4. The number of favorable outcomes is exactly 1 and the number of all possible outcomes is 5·4=20 (you have 5 ways to select 1st slip and 4 ways to select 2nd slip). Then the probability of event
is

2. The event
consists in selecting two slips with the sum 4. The number of favorable outcomes is exactly 2 (1st slip 3 and 2nd slip 1 or 1st slip 1 and 2nd slip 3) and the number of all possible outcomes is 5·4=20 (you have 5 ways to select 1st slip and 4 ways to select 2nd slip). Then the probability of event
is

3. Then

Answer: 
Answer:
sorry I didn't knew it was calculus.
Answer:
1+12x or
13
Step-by-step explanation:
If the x is an expression then
4+ (-3) - 2x (-6)
remove first parenthesis
4-3-2x(-6)
2 negatives = a postive
4-3+2x*6
multiply
4-3+12x
substract
1+12x
4+ (-3) - 2x (-6)
remove first parenthesis
4-3-2*(-6)
multiply
4-3+12
substract
1+12
add
13