Block a sits on block b with weight of 20 and 50 lbs. If the coefficients of static and kinetic friction between all surfaces are μs = 0.4 and μk = 0.3, determine the acceleration of each block if p = 9lbs

The brightest star in the night sky in the northern hemisphere is sirius. its distance from earth is estimated to be 8.7 light years. a light year is the distance light travels in one year. light travels at a speed of 3.00 × 108 m/s. calculate the distance from earth to sirius in miles. (1 mi = 5280 ft) g