How do know how many protons are in a atom

The circumference of a circle is 36 pi feet. What is the length of the radius of this circle?

Which is a solution to the equation 5x - y = - 3? A. (-2, 7) B. (2, - 7) C. (-2, - 7) D. (1, 2)

There are three schedule options for classes at a high school: 90-minute classes every other day for a year, 90-minute classes every day for a semester, or 45-minute classes every day for a year.

What is 3x^3+21x^2+30x=0?

Cynthia bought some grapes on sale for $.94 per pound. if she paid 2.35 for the grapes. how many pounds of grapes did she buy

At a currency exchange, 3 u. s. dollars can be exchanged for 5 japanese yin. how many yin will you receive for 1 u. s. dollar?

What is the volume of 20 grams of an object with a density of 55g/cm^3?

I need the answer 5x-6=14

A ball is dropped from a height of 100 inches the ball bounces, each time reaching a lower and lower height.

A dress just went on sale and is 20% Off. To return to its previous price, How much in percentage should the price be raised?