Half of the sum of a number and 6 is no less than 20

In the sixth grade 13 out of 20 students have a dog if there are 152 sixth grade students how many of them have a dog

Aliter of water contains about 3.35 x 10^25 molecules. a certain river discharges about 2.9x 10^8 l of water every second. about how many molecules does the river discharge every minute? write your answer in scientific notation

Which of the following is true about the following construction of a tangent to a circle from a point outside of the circle?