Answer:
variable
Step-by-step explanation:
A variable is a American, Latin, Greek etc letter used to represent an unknown.
Answer:
100
Step-by-step explanation:
500ml÷5h=100ml/h
Answer:
An equation is 
Step-by-step explanation:
Let
be the measure of the unknown acute angle.
According to angle sum property of a triangle, sum of all the angles of a triangle is equal to 180°.
One of the acute angles of a right triangle is equal to 52°.
Also, the triangle is a right angled triangle, one of the angle must be equal to 90°.

So, an equation is 
0....1/4..... 2/4 or 1/2 ..... 3/4..... 1.... 1 1/4.... 1 2/4 or 1 1/2...... 1 3/4..... 2.... and so on and so on