How can one talk without saying a single word?

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

I am a type of vehicle that has two wheels and is powered by humans. What am I?
Hint 1: You can ride me for exercise.
Hint 2: I am environment-friendly.

In which direction should the missing arrow point?

John and Jill are madly in love with each other. To remind Jill of his pure love, John wants to send her a ring by post but in their country where burglary is quite prominent, any package that is not locked comes under the risk of being stolen for the contents.

John and Jill possess many padlocks but neither one of them has the other key.

Can you find a way John can send the ring to Jill safely?

Can you place six matchsticks in a manner that each of the matchsticks is in touch with the other five matchsticks?

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

Find the missing letter in the last circle logically in the given below picture.

Can you find the dog hidden in a group of pandas?

I was speeding and ran through a stop sign, yet two traffic officers who were there do nothing about it.

why?