How to implement In memory cache from angular front with graphql Queries?

I have angular frontend application, we are fetching data with graphql queries using apollo client.
We want to implements caching to fetch the data.
Only first time we need to query the data and it should stored in cache , while calling the same next time the data should be returned from the cache.
If any updates in data, it should call the query and should return the data.have written a graphql query to fetch the data.
Need to know how to implement in memory cache.