Chemistry Exam HELP. no fake answers please

Suppose a lab group reports a ppercent yield of sand of 105. is it really possible to collect more sand than was originally represented? what is the possible explanation for the extra product?

Scientists often deal with numbers that are either very large or very small. for example, the radius of the sun is approximately 696,000 kilometers, while bacterial cells are as small as 1.9 × 10-4 millimeters. express each of these numbers in an alternate form.

The temperature of a lead fishing weight rises from 26 °c to 38 °c as it absorbs 11.3 j of heat. what is the mass of the fishing weight in grams?