Questions about the ionosphere... is gravity lying under it? how does that operate the whole gravity limited by the perimeter of I think it's the ionosphere? correct?

When describing down syndrome, it's important to note that a. it can be classified as a single-gene disorder b. it is caused when red blood cells cannot properly form hemoglobin c. it causes infected males to have low testosterone levels d. it is usually caused by three copies of chromosome 21 select the best answer from the choices provided. a b

Your target variable is δf, the magnitude of the difference in frequency between the waves emitted from the sonar device and the waves received by the device after reflecting off the whale. write an expression for δf in terms of the relevant frequencies using the subscript notation introduced above.

Which statement best describes copper? a. it has a low resistance and prevents charges from moving freely. b it has a high resistance and allows charges to move freely. c. it has a high resistance and prevents charges from moving freely. d. it has a low resistance and allows charges to move freely