Two crates, one with mass 4.00 kg and the other with mass 6.00 kg, sit on the frictionless surface of a frozen pond, connected by a light rope ($\textbf{Fig. P4.39}$). A woman wearing golf shoes (for traction) pulls horizontally on the 6.00-kg crate with a force $F$ that gives the crate an acceleration of 2.50 m/s$^2$. (a) What is the acceleration of the 4.00-kg crate? (b) Draw a free-body diagram for the 4.00-kg crate. Use that diagram and Newton's second law to find the tension $T$ in the rope that connects the two crates. (c) Draw a free-body diagram for the 6.00-kg crate. What is the direction of the net force on the 6.00-kg crate? Which is larger in magnitude, $T$ or $F$? (d) Use part (c) and Newton's second law to calculate the magnitude of $F$.