WACC THEORY - MV & BV INCOMPLETE INFO

Firstly… sorry for asking this question the millionth time (I assume it has been asked and my inability to find the answer high)

Given…

MV Equity : 100

BV Equity : 75

BV Debt: 40

MV Debt: Not Given, not implied, nothing…

To calculate the weights, do we use

BV(E)/ BV(E) + BV(D) -> assumption that book values must be compared to book values (like for like) ?

or …

MV(E) / (MV(E) + BV(D) -> mix and match… use the Market value for equity but the BOOK value for debt (since we dont have market)

Thank You!

mix and match

thank you - you’re the best!