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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

Given the position vector of the particle r(t)=(t+1)i+(t^2−1)j+2t k, find the particle's velocity and acceleration vectors at t=1

Which articulations allow for greatest range of motion?