I need help with two please I’m in chapter.
9.1 Characteristics of life

Complete the following reactions using word and balanced equations including states. dilute phosphoric acid is added with a calcium hydroxide solution.

What are the charges of the subatomic particles by choosing the answer from the drop down menu. protons have a (+1,0,or-1). (protons, neutrons, electrons) have a 0 charge. 3.) electrons have a (+1,0,-1)

Significant figures are digits read directly from the measuring instrument plus one more digit, which is __ by the observer.