Ametric in a two dimensional spacetime with coordinates (u, v) is transform the line element ds2 from (u, v) to new coordinates (a, t) defined by t=usinh u, cosh u, x= and determine the curvature tensor rasu for this spacetime

In which situation is the acceleration of a car negative? question 5 options: a)the velocity of a car was 75 km/hr over 4 hours. b)the velocity of a car reduced from 50 km/hr over one minute. c)the velocity of a car increased from 40 km.h to 75 km/h over 15 minutes. d)the velocity of a car was 45 km/hr at 2: 00pm and at 4: 00pm its velocity was 85 km/ht.