MCQ
The double helical structure of $DNA$ was proposed by
- ✓Watson and Crick
- BMeicher
- CEmil Fischer
- DKhorana
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| List $-I$ (Compounds) | List $-II$ (used in) | ||
| $(A)$ | $BaSO_4 +ZnS$ | $(1)$ | Explosive |
| $(B)$ | $NI_3$ | $(2)$ | Oxidiser in rocket propellants |
| $(C)$ | $N_2O_4$ | $(3)$ | Space capsule |
| $(D)$ | $KO_2$ | $(4)$ | Pigment |
Product $\mathrm{P}$ is