What is 80,000,000 +4,000,000+100+8 in standard form

Which best explains why this triangle is or is not a right triangle?

If x = -2, then x 2-7x+10 equals a. 0 b.20 c.28

Circle a has a diameter of 7 inches, a circumference of 21.98 inches, and an area of 38.465 square inches. the diameter of circle b is 6 inches, the circumference is 18.84 inches, and the area is 28.26 square inches. part a: using the formula for circumference, solve for the value of pi for each circle. (4 points) part b: use the formula for area and solve for the value of pi for each circle. (4 points)