PLEASEEE …. HELPPP MEEE!!!

Maybe for you this is a simple problem, but for me is not.

i have friend who is christian and not live at Indonesia. He love to know islam and make so many question about it, but sometimes i dont know how i can explain to him. i know i have to study again why its forbid or allow in Islam rule, bec Islam rule based from logic and health.

such as :

1. why muslim not allowed to have dog as their pet, why Muhammad more love cat as his pets?

2. why muslim not allowed to married with a person who have different religion?

please help me with this…and can u explain in health perception for the 1 issue!!! and in english…

i will show this to my friend and he will know why Islam not allowed and see Islam in different way!

thanks before and after…!