Aperson is walking briskly in a straight line, which we shall call the x axis. figure 2.42 shows a graph of the person's position x along this axis as a function of time t.

Could someone . i have tried to solve myself but my calculation is off

Photoelectrons with a maximum speed of 6.50 x 107 m/s are ejected from a surface in the presence of light with a frequency of 6.75 x 1014hz. if the mass of an electron is 9.10 x 10-31 kg, calculate in joules the maximum kinetic energy of a single electron. 3.84 x 10-15 j 1.92 x 10-15 j 5.92 x 10-23 j 3.07 x 10-16 j

7.45 a student is interested in the aerodynamic drag on spheres. she conducts a series of wind tunnel tests on a 10-cm-diameter sphere. the air in the wind tunnel is at 50 â°c and 101.3 kpa. she presents the results of her tests in the form of a correlation, đť’ź = 0.0015v1.92, where đť’ź is the drag force in newtons and v is the velocity in m/s. another student realizes that the results would have been more effectively presented in terms of dimensionless parameters, say, î  1 = f (î  2) = c î  a2 , where î  1 and î  2 are dimensionless parameters and c and a are constants. what are the most appropriate dimensionless parameters (î  1 and î  2) and the corresponding values of c and a? what would be the drag on a 2-cm-diameter sphere placed in a 1-m/s, 20 â°c water stream?