Use substitution to solve the following system of equations. Show all of your work. Write the solution as an ordered pair.

Divide: 1573 ÷ 7 = a) 222 r5 b) 223 r6 c) 224 r5 d) 224 r3

What is the measure of angle afe? 79 81 91 99

The average human heart beats 1.15 \cdot 10^51.15⋅10 5 1, point, 15, dot, 10, start superscript, 5, end superscript times per day. there are 3.65 \cdot 10^23.65⋅10 2 3, point, 65, dot, 10, start superscript, 2, end superscript days in one year. how many times does the heart beat in one year? write your answer in scientific notation, and round to one decimal place.