Answer:
No; 1,100 will cause him to exceed 1,900.
Explanation:
The rationale for this problem is basic.
Jace established a diet restricted to 1900kcal.
If he started 1500kcal and burned 400kcal in the gym, Jane's partial jump is 1100 calories.
Thus, it can still eat the total of 1900-100 = 800kcal.
Any value over 800kcal will exceed the tax threshold and will disrupt Jane's results.