A student is measuring the circumferences of pine trees for an experiment. She measures 50 trees using a ruler that measures to the nearest centimeter.
Which statement describes a change that could help improve the results of
her experiment?
A. Her measurements will be more precise if she measures an
additional 50 trees.
B. Her measurements will be more accurate if she uses a cloth tape
measure instead of a ruler.
C. Her measurements will be more precise if she uses a cloth tape
measure instead of a ruler.
D. Her measurements will be more accurate if she measures an
additional 50 trees.

B and C

Explanation:

The student's measurement would be more accurate if she can measure an additional 100 caterpillars and be more precise if she uses a ruler that measures to the nearest millimeter.

Accuracy refers to the closeness of measurement or group of measurements to the true value while precision is the closeness of repeated measurements.

The accuracy of a measurement is increased by increasing the number of sample measurements. The more the sample measurements, the lesser the deviation of the mean from the true value.

The precision of a measurement is increased by being able to measure small differences. Hence, a ruler that measures to the nearest millimeter would be more precise than a ruler that can only measure in centimeter.

The correct option is B and C.

frequency or wavelenth of em radiation in a vacuum

answer: the metamorphic rocks are formed when they are exposed to high pressure and high temperatures. this happens when one of the earth's plates comes in contact with the other plate by traveling in opposite directions, straight into each other or slipping under one another. the friction that is caused by this activity results in   melting of rocks and when it cools they are known as metamorphic rocks. this process needs a controlled amount of pressure and temperature otherwise it may turn into magma.