The first thing we must do for this case is find the number of total guitarists.
We have then:

We now look for the relationship between the number of guitarists playing jazz alone to the total number of guitarists.
We have then:

Where,
x: number of guitarists playing jazz alone
From here, we clear the value of x.

Then, the number of guitarists who play classical solo is:

Answer:
30 guitarists play classical solos in the contest
Answer:
Its -1.9 for where point D is
Answer:
The mean is 70, that's all I know. Sorry!
Step-by-step explanation:
Here's how you find the mean:
1. Add together ALL NUMBERS. (which equals 560 in this case.)
2. DIVIDE by the amount of numbers there are. (So 560 ÷ 8 = 70)
3. There's your answer! The mean of these numbers is 70.
I really hope this helps! Have a great day\night!
It’s 9b it’s just 4+5 with the b