What does does this rebus picture means ?

A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

How many times in a given day, minutes and hour clock comes in a straight line ?

I am quite hot but become too cold if you remove the first two letters. What am I?

There is a circular car race track of 10km. There are two cars, Car A and Car B. And they are at the exact opposite end to each other. At Time T(0), Both cars move toward each other at a constant speed of 100 m/seconds. As we know both cars are at the same speed they will always be the exact opposite to each other.
Note, at the center, there is a bug which starts flying towards Car A at time T(0). When the bug reaches car B, it turns back and starts moving towards the car A. The speed of bug is 1m/second. After 5 hours all three stop moving.
What is the total distance covered by the bug?

Analyze and find the missing item in the sequence:
16, 06, 68, 88, __, 98

A father's child, a mother's child, yet no one's son.

Who am I?

I came first on earth but second on the heaven.
I also came twice in a week but found just once in a year.
I stay away from months but you can find me in February.

What am I?

Take away the whole and some still remain. What is it?

Lady Gaga is pregnant and currently has 6 daughters

1. Dorry 2. Rebeka 3. Michael 4. Faniya 5. Sophia 6. Lavanya

What will she name her next child girl? (Think Logical)

A. Neema B. Tanya C. Tisha D. Jenniffer