An atom of element a has 71 protons. what would the element's atomic number be?

Which of the following expressions is equivalent to -1/4y - 2 1/4 + 1/2 (4-2y)? a. -3y + 2b. -3 1/2+4c. -4 1/2y+2d. -4 1/2y+2show ur work

What would be the distance of all the planets to the sun in astronomical units?

Which of the following statements best characterizes changes to agriculture in the united states since 1900? a. increased mechanization has reduced the need for labor. b. increased mechanization has increased the need for water, thereby increasing the need for labor. increased mechanization has increased the use of land, thereby increasing the need for labor. d. increased mechanization has increased food production, thereby increasing the need for labor. select the best answer from the choices provided.