HI!
Can you guide to which equation to use for this problem:
An electron with the speed of 2 x 10^7 m/s enters a magnetic field with a velocity vector 25^0 away from the magnetic field direction. If it experiences an acceleration of 1.5 x 10^16 m/s^2, determine (absolute value) B.
First compute the force.
F = m a,
in Newtons
Then use F = e V B sin 25 to get the field strength B, in Tesla.
You will need to use the mass, m, and the charge, e, of the electron. These are readily available.