Which of the following is NOT a possible cause of a genetic disorder in humans?

changes in the number of chromosomes

mutations in the DNA of genes

being born underweight

changes in the structure of chromosomes

What property of a wave describes how often it occurs?

A car went 346 miles in 6 hours, traveling part of the time at 55 miles per hour and part of the time at 65 miles per hour. How long did the car travel at each speed?

A fourth-grade teacher wants to ensure students understand the life cycle process of plants. The teacher decides to incorporate the science-as-inquiry standard from the National Education Science Standards.

What is the term for the positive charge in an atom? A. Proton B. Electron C. Nucleus D. Fulcrum F. Disequilibrium

Which of the following items would have the lowest density? OA. A 12 cm3 block of aluminum with a mass of 2 grams OB. A6 cm3 block of ice with a mass of 4 grams OC. A 12 cm3 block of wood with a mass of 3 grams OD.

a boy hears the echo of his own voice from a distance hill after 0.8 seconds. If the speed of sound in air is 340m/s, calculate the distance of the hill from the boy.

Which of the following are found in plant cells buh not animal cells?

The diagram shows the field lines near the poles, X and Y, of two magnets Based on the field lines, what are the poles of the magnets? O X: north Y south X: south Y north X north Y north Х Y X south Y south

Why is it safe to watch an eclipse of the Moon but not an eclipse of the Sun

A student holds two pieces of paper at the top, 10 cm apart. The flat sides of the papers face each other. What happens when the student uses a straw to blow a stream of air between the papers?