Decode this picture on T-Shirt and tell what it says ?

You are given with the following sum. Each of the letters can be decoded as a digit. If we tell you that D = 5, then can you solve it entirely?

DONALD
+GERALD
=ROBERT

I’m tall when I’m young, and I’m short when I’m old. What am I?

By using 'because' continuously three times, can you make an English statement ?

Can you name any English verb that becomes its past tense by simply rearranging the alphabets ?

Forwards I am heavy, backward I am not. What am I?

I am lying and I always lie. Tell me whether I am lying or telling the truth.

Pronounced as 1 letter, And written with 3, 2 letters there are, and 2 only in me. I’m double, I’m single, I’m black blue and grey, I’m read from both ends, and the same either way. What am I?

You have 10 balls with you. A friend of yours out of nowhere asks you to place those ten balls in five lines such that each of the lines has exactly 4 balls on them. He needs to check your intelligence. Prove him by doing the task.

I am the fastest animal but cannot climb the tree. What am I?