You are given two tables. **Table: `calls`** - `call_id` BIGINT - `sender_id` BIGINT - `receiver_id` BIGINT - `call_ts` TIMESTAMP — stored in UTC - `pickup` CHAR(1) — `'Y'` if the call was picked up, `'N'` otherwise - `call_type` VARCHAR — either `'video'` or `'voice'` Assume each row represents one call attempt. **Table: `users`** - `user_id` BIGINT - `country` VARCHAR Assume `calls.sender_id = users.user_id` when you need the caller's country. Unless otherwise stated, compute results over the full available dataset. Write SQL for the following: 1. Return the total number of calls and the number of picked-up calls for each `call_type`. - Output columns: `call_type`, `total_calls`, `picked_up_calls` 2. For a given country parameter, compute the percentage of calls placed by senders in that country that were picked up. - Output columns: `country`, `pickup_rate_pct` - Treat `pickup_rate_pct` as `100.0 * picked_up_calls / total_calls` 3. Compute the percentage of distinct callers who have made at least one `video` call and at least one `voice` call. - Denominator: all distinct `sender_id` values in `calls` - Output column: `pct_callers_both_types`