help i dont know the formula for the triangle to find the answer its surface area n volume

Answer:
#4=10.5
#5=48
Step-by-step explanation:
The formula for the triangle for area is 1/2 time base times hight
The forumale fot the triangle for volume is 1/2 time base times hight
So for number #4 it will be 1/2 x 3 x 7
and number #5, it will be 1/2 x 8 x 12