Answer:
c. Skewed-right with a mean of $5.25 and a standard error of$0.28
Step-by-step explanation:
As we have given that Sales prices of baseball cards have a right-skewed distribution with a mean $5.25 and a standard deviation is $2.80.
Now, We know that if standard deviation = σ
then, standard error = 
As, we have standard deviation = $2.80
then standard error will be
⇒ Standard error = $0.28
Hence, Option (c) is the correct option.
Answer 3
This is because there is three cups of flower and she uses a tablespoon of salt for each cup
7^2 = 6^2 + 9^2 - 2(6)(9)cos(m)
-68 = 2(6)(9)cos(m)
cos(m) = -0.6296
m = arcos ( -0.6296)
m = 129.0 degrees