Competitive bidding after 1NT

Question 1

1NT, double,
???

Answer 1

all systems are still on
Redouble forces opener to bid 2♣️, correctible to 2♦️

Question 2

1NT
any bid
???

Answer 2

Stayman and Jacoby transfers are off systems are off
2 level bid shows 0-7 points and 5+ cards

Question 3

1NT, pass
2♣️, 2♦️ / 2♥️
???

Answer 3

Bid 4-card major at 2 level (2 spades)

Question 4

1NT
pass
2♦️ / 2♥️
double
pass

Answer 4

Shows <3 trump support

Question 5

1NT
pass
2♦️ / 2♥️
double
redouble

Answer 5

Shows strong holding in doubled suit