Which statements about the histogram are true check all that apply

The histogram shows that nine students had grades 80 or higher
B
C
D

Please help

Avery’s piggy bank has 300 nickels, 450 pennies, and 150 dimes. she randomly picks three coins. each time she picks a coin, she makes a note of it and puts it back into the piggy bank before picking the next coin.

What expression is equivalent to (84+16)

For the sequence [tex]a_{n} = 2n/(n+1)[/tex], what is the value of [tex]a_{10}[/tex]