Answer:
7 millimeters
Step-by-step explanation:
Volume is the area of the base times it's length.
140/10 is 14
so the area of the triangle is 14
the formula for area of a triangle is base times height divided by 2
so
d x 4/ 2 = 14
multiply both sides by 2
d x 4 = 28
divide both sides by 4
d=7
