Calculate the percent composition (percent by mass of each element) of NH4Cl. Round to the nearest ONES place ((example: 12.34% = 12%))

For ai it's atomic number is 13 and it's mass number is 27 how many neutrons does it have

Sarah wants to know where in her garden chamomile would grow the best. she thinks chamomile will grow best in the corner of the garden that gets the most sunlight. to test her hypothesis, she decides to plant several groups of chamomile in her garden as an experiment. which of the following variables will sarah need to measure to know which group of plants grew best? a. the location of the plants b. the type of plants c. the height of the plants d. the amount of water she gives the plants

Will mark brainliest how many electrons can be held in the energy level n = 4?