Is it ....A Flock ... of Hippos?

Clearly it is  (collective noun) of hippos swimming across the River Oose, near St Ives.

But what is the correct collective noun for swimming hippos?

My brain says "A School Of..."  but I'm not 100% sure.

Bonus - US troops testing a panzerfaust on a knocked out Tiger II.

Bonus 2 -

Probably Not St Ives, Cornwall.

A fine shot of three of Reginald Iolanthe Perrin's Mother-In-Laws, but despite being in the same box of slides as yesterdays, I doubt this shot was taken in Cornwall.

Dorset, perhaps.

Bonus - Ying and Yang

Bonus 2 - MAGA - Making America Ghastly, Always

Reggie's Mother-in-Law (and chums)

 Heavens, that is a fairly old reference. If any of you YooKay readers don't understand, ask a grandparent about Reggie Perrin.
Non-YouKay readers -  don't worry,the humour will be lost on you.

As mentioned yesterday, this slide is front an African safari series.

Bonus - Genetic Cars - Very...umm....engineery

Reggie's M-I-L

I assume that I don't have to explain that reference.

Bonus : Red Hot Nickel Ball In Water (Sound volume - Up.)